Detection Of Hogwash Oil Based On Animal Genetic Information

Hogwash oil represented great potential harzard to food safety and public health, however the standard detecting method has not yet been formed. In this study, we explore a new detection method of hogwash oil by analysing animal genetic information. According to the source of hogwash oil, we know that the animal ingredients would be inevitably mixed in most hogwash oil. First of all, the attenuation rule of the main animal genetic information through oil refining process was discussed, then the detection limit and detection situation of four kinds of animal genetic information in the oil were studied based on PCR. Finally, a more feasible detection technology of animal information was confirmed by blind verification and a new technology reference for hogwash oil was provided. The main conclusions were as follows:(1) In view of four kinds of animal meat in the food chain, and DNA concentration and purity as indicators, two pretreatment methods in the process of extracting DNA were compared. The result show that after the vacuum freeze drying processing before extracting, the concentration and purity of DNA were higher and better.(2) By simulating the oil refining process, after degumming, decoloring and deodorization, chicken oil as the represented animal oil was studied to get the attenuation of DNA information. The result showed that DNA content of chicken oil and lard oil decreased by 9.5% and 11% respectively after refining processing, and the losses of animal genetic information would be brought.(3) Research of detection limit about different animal oils: by setting 10%, 5%, 1%, 0.5% and 0.1%(m/m) of single animal oil(lard, bovine, sheep and chicken oil) mixed with edible oils, DNA was used with the silica spin column for miniprep to extract from oil. The result showed that the method based on PCR technology could be detected 0.1%(m/m) of single animal oil in edible oil.(4) Test of detecting and identifing oils blended with different kinds of animal oils: by adulterating two, three and four kinds of animal oils with edible oil respectively, then DNA was extracted for PCR amplification. The result showed that only the corresponding animal information had its amplification without interference, and and its corresponding animal information detection limit also was 0.1%(m/m). Thereby, the technology could be used to analyse and identification of the mixed oils and to judge suspected hogwash oil.(5) Blind validation test: six kinds of blind samples mixed different animal oils for analysis were man-made by mixing with different proportion animal oils in edible oil. The result showed that the detection rate was 100%, and the identification accuracy was 92%. Moreover, the established method based on PCR technology of detecting edible oil mixed with animal oil was feasible, and could be used for preliminary screening of hogwash oil.